Solid smart contract development - 3.3-solid syntax control structure

solidity The control structures of are if, else, while, do, for, break, continue, return. These keywords are in the C Language and JavaScript The expression is the same in , Learn these three axes well, and all the logical structures are easy to realize .

1. if-else

function test(uint256 _number) public pure returns(bool){
    if(_number == 0){
        return(true);
    }else{
        return(false);
    }
}

2. for loop

function test() public pure returns(uint256){
    uint sum = 0;
    for(uint i = 0; i < 100; i++){
        sum += i;
        if(sum > 50){
            break;
        }  
    }
    return(sum);
}

3. do-while loop

function test() public pure returns(uint256){
    uint sum = 0;
    uint i = 0;
    do{
        if(sum < 10){
            continue;
        }
	    sum += i;
	    i++;
    }while(i < 100);
    return(sum);
}

4. use solidity Implement insertion sort  

 //  Insertion sort 
    function insertionSort(uint[] memory a) public pure returns(uint[] memory) {
        // note that uint can not take negative value
        for (uint i = 1;i < a.length;i++){
            uint temp = a[i];
            uint j=i;
            while( (j >= 1) && (temp < a[j-1])){
                a[j] = a[j-1];
                j--;
            }
            a[j] = temp;
        }
        return(a);
    }